The present invention relates to a nut delivery apparatus for a high speed nutcracker and which achieves a high degree of efficiency in picking up and cracking the nuts.
U.S. Pat. Nos. 4,332,827; 5,623,867; 6,182,562; 6,205,915; 6,270,824; 6,584,890, 6,588,328; and 6,772,680 all disclose a high speed nutcracking apparatus which includes a rotatable turret which mounts a plurality of cracking units arranged about its periphery, with each cracking unit having an opening adapted to receive an individual nut from a feed conveyor which comprises a plurality of nut transport elements mounted in succession on a feed chain. Each of the nut transport elements includes an upwardly open transverse receptacle for holding an individual nut, and each cracking unit on the turret has an anvil which is moved axially into the receptacle at a pick up point so that the nut is engaged between the anvil and a crack die on the other side of the opening.
In operation, the feed conveyor moves tangentially past the rotating turret so that the anvils of the cracking units enter the receptacles of respective nut transport elements at the pick up point and engage and pick up the nut. After the cracking unit and engaged nut have moved away from the pick up point and reach a cracking location, the crack die of the cracking unit is impacted by a shuttle so that the crack die applies an impact to the nut to crack the shell.
As will be apparent, it is important that the nut delivery system be able to deliver a single nut in the receptacle of each nut transport element, and that the nut be oriented with its end to end direction aligned in the receptacle. To achieve this objective, the prior feeding systems include an arrangement to singulate and orient the nuts as they are received in the receptacles of the nut transport elements and as the elements move through the hopper. For example, and as disclosed in U.S. Pat. No. 6,205,915, the hopper includes an orienting deflecting plate which is designed for laterally deflecting the upper portion of any upstanding nuts disposed in each receptacle. To singulate the nuts in each receptacle, there is provided a singulating arm in the form of a wire which extends into a slot in one side of each of the advancing nut transport elements, and which serves to laterally eject any laterally oriented nuts in excess of one from each receptacle. The wire arm is mounted for pivotal adjustment about a mounting pin.
Pecans vary significantly in size, and they are typically run through a sizing machine prior to cracking so as to separate the nuts into different grades. To adjust the singularizing and orienting arrangement to efficiently process nuts of different sizes, the singulating wire arm as shown in FIG. 3 of the '915 patent is pivotally adjusted to vary the distance the arm extends into the slots of the advancing nut transport elements. Thus for smaller nut grades, the arm is pivoted to extend further into the slots, and for larger grades, the arm is pivoted to extend a lesser extent into the slots.
In copending application Ser. No. 11/201,827, filed Aug. 11, 2005, an improvement is disclosed wherein the singulating wire arm is replaced with a flat singulating arm which extends laterally into the slot of each advancing element. Also, an actuating member which is located on the outside of a side wall of the hopper is provided for adjusting the lateral extent to which the arm extends into the slots of the advancing elements. The adjustment of the machine to accommodate nuts of different grades is thereby greatly facilitated.
The orienting deflecting plate as disclosed in the '915 patent comprises a rigid metal bar which is mounted for pivotal movement about a horizontal axis at the upstream end of the bar, and the downstream end portion of the bar comprises a thin metal extension plate which is sufficiently thin to permit it to be easily bent to closely conform to the arcuate path of the feed chain as it moves from an upwardly inclined direction to a horizontal direction which extends tangentially past the lower portion of the turret. The arcuate extension plate serves to prevent the nuts from lifting from the nut transport elements as the nut transport elements move rapidly through the arcuate juncture.
The thin metal extension plate as described above is problematic in a number of respects. For example, if the machine operator should rotate the turret in a reverse direction in the course of a maintenance procedure, the feed chain will also move in the reverse direction since its drive is interconnected with that of the turret, and the forward end of the extension plate can be caught on the upper rear corner of a nut transport element of the feed chain, causing the extension plate to bow upwardly and be permanently bent. When this happens, it is often necessary to replace the entire extension plate.
A further problem associated with the prior extension plate is the fact that occasionally two or more nuts are received in the receptacle of a nut transport element, and such double feed of the nuts will reach the extension plate and be delivered to the pick up point where the nuts are dropped without being cracked. Also, when this happens, the extension plate will be lifted by the nuts, which causes the entire deflecting plate to lift upwardly. This in turn permits additional double feeds to enter under the deflecting plate, and the condition is repeated and becomes self-perpetuating.
The embodiment of the apparatus disclosed in U.S. Pat. No. 6,205,915 also includes an adjustable support plate which supports the nut transport elements as they advance in a horizontal direction toward and across the nut pick up point on the turret. The support plate is adjustable in elevation by pivoting it about a pivot axis, so that the elevation of the receptacles of the nut transport elements as they move past the pick up point can be adjusted to accommodate nuts of different sizes.
During operation of the apparatus as disclosed in the '915 patent, it has been found that the anvil of a cracking unit can fail to retract during operation. While this failure to retract is rare, it can cause damage to the support plate when it occurs. In particular, when the anvil fails to retract and remains in the nut receiving opening of the cracking unit, it will strike the nut in the nut transport element at the pick up location with sufficient force to permanently bend the underlying support plate. The support plate often then needs to be replaced.
It is accordingly an object of the present invention to provide an improved high speed nutcracking apparatus which avoids the problems associated with the prior machines as noted above.
It is a more particular object of the present invention to provide a high speed nutcracking apparatus of the described type and which includes an improved and more reliable system for orienting the nuts in the nut transport elements as they move toward the delivery point, and to thereby achieve an improved feed efficiency.
It is also an object of the present invention to provide an improved support plate for supporting the nut transport elements as they move past the delivery point, and which is not susceptible to bending from an impact resulting from an anvil which has failed to retract from the nut receiving opening of a cracking unit.